docs: def get_variogram_points(self):
          """Returns both the lags and the variogram function evaluated at each
          of them.
  
          The evaluation of the variogram function and the lags are produced
          internally. This method is convenient when the user wants to access to
          the lags and the resulting variogram (according to the model provided)
          for further analysis.
  
          Returns
          -------
          (tuple) tuple containing:
              lags (array) - the lags at which the variogram was evaluated
              variogram (array) - the variogram function evaluated at the lags
          """
          return self.lags, self.variogram_function(self.variogram_model_parameters, self.lags)